问输入字段中的jQuery验证错误消息在焦点处消失。

EN

<form id="lead">
<input type="text" name="first_name">
<input type="text" name="last_name">
<input type="email" name="email">
<input type="submit">

    $(function () {
    //Validation
    $('#lead').validate({
        rules: {
            first_name: {
                minlength: 2,
                required: true
            },
            last_name: {
                minlength: 2,
                required: true
            },
            email: {
                email: true,
                required: true
            }
        },
        errorPlacement: function (error, element) {
            element.val(error.text());
        },
        messages: {
            first_name: "Enter your first name",
            last_name: "Enter your last name",
            email: "Enter your email"
        },
        submitHandler: function (form) { // for demo
            alert('valid form submitted'); // for demo
            return false; // for demo
        }
    });

});